He has a tough fight against former State Senator Richard Tisei, who isn’t shy about throwing the saga of Tierney’s racketeering in-laws and tax-return-falsifying wife in his face. But that case and the brother-in-law’s sensational new charges have something in common: A lack of actual evidence implicating Tierney.

Congressman John Tierney spoke on the phone with WBZ, refuting allegations by his brother-in-law that he knew all about the illegal offshore gambling ring that wound up sending Tierney’s wife and now her brother to jail.

“I wasn’t implicated in any way shape or form in that,” says Rep. Tierney. “I’ve been busy doing my job down here (in Washington D.C.) and fighting for people and small businesses in my district and doing it well and I think that’s what people are going to respond to when it comes time to vote in November.”

Challenger Richard Tisei once said he wouldn’t make a campaign issue of the Tierney family’s legal woes. But he’s now taking his cue, he claims, from skeptical voters.

“It definitely concerns me,” said one voter, “because as a voter you want honest people in the system.”

“It definitely will be a big factor just because it is kind of as big deal,” said another voter. “You do need people who are honest that are running.”

Tisei says voters don’t expect politicians to be perfect, but they “expect them to be honest and forthright.”

So will the accusations hurt Tierney? “I think that assessment will come up at the polls,” says the congressman.

Early polling showing a competitive race and a recent decision by the national GOP to pour ad money into the contest reflect the fact that the family troubles have hurt the incumbent. That may not be fair to Tierney, but nobody ever said politics was fair.